The present invention is concerned with improvements in or relating to sole attaching, in particular the attachment of a sole to the bottom of a shoe by means of adhesive composition. The word "shoe" is used herein generically to include outer footwear generally whether complete or in the course of manufacture, and the word sole is used herein to include sole and heel units formed in one piece or assembled prior to attachment to shoes.
It is a well-known operation in the manufacture of shoes having a sole attached by means of adhesive composition to apply pressure thereto after the sole has been positioned on the bottom of the shoe in order to effect a firm bond. Shoes differ widely in shape and style and it is desirable in the sole attaching operation that a relatively big change from one shoe bottom shape to another can be quickly accommodated.
Machines for applying bonding pressure to shoes in order to adhesively bond the sole to the shoe bottom have comprised a shoe bottom pressing arrangement on which the shoe is supported, and depending presser members against which the shoe may be held by means by hydraulic pressure urging the shoe bottom pressing arrangement towards the depending presser members. Due to the considerable variety of shapes and sizes of shoes to be operated on, it has been a usual practice to provide interchangeable shoe bottom pressing arrangements for machines of this kind. Frequent changes of the arrangements may thus be needed during normal shoe factory production conditions, requiring either replacing the arrangement with another more suitable one, or detailed interchange of elements of the arrangement, thus potentially resulting in loss of production time and in inaccurate setting of the arrangement to the requirements for a given shoe. The wide variety of lengthwise and transverse curvatures encountered especially in the waists of shoes accentuates this problem.